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Diffstat (limited to 'arch/mips/include/asm/syscall.h')
| -rw-r--r-- | arch/mips/include/asm/syscall.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/mips/include/asm/syscall.h b/arch/mips/include/asm/syscall.h new file mode 100644 index 000000000..6cf8ffb53 --- /dev/null +++ b/arch/mips/include/asm/syscall.h @@ -0,0 +1,160 @@ +/* + * Access to user system call parameters and results + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * See asm-generic/syscall.h for descriptions of what we must do here. + * + * Copyright (C) 2012 Ralf Baechle <ralf@linux-mips.org> + */ + +#ifndef __ASM_MIPS_SYSCALL_H +#define __ASM_MIPS_SYSCALL_H + +#include <linux/compiler.h> +#include <uapi/linux/audit.h> +#include <linux/elf-em.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/uaccess.h> +#include <asm/ptrace.h> +#include <asm/unistd.h> + +#ifndef __NR_syscall /* Only defined if _MIPS_SIM == _MIPS_SIM_ABI32 */ +#define __NR_syscall 4000 +#endif + +static inline bool mips_syscall_is_indirect(struct task_struct *task, + struct pt_regs *regs) +{ + /* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */ + return (IS_ENABLED(CONFIG_32BIT) || + test_tsk_thread_flag(task, TIF_32BIT_REGS)) && + (regs->regs[2] == __NR_syscall); +} + +static inline long syscall_get_nr(struct task_struct *task, + struct pt_regs *regs) +{ + return current_thread_info()->syscall; +} + +static inline void mips_syscall_update_nr(struct task_struct *task, + struct pt_regs *regs) +{ + /* + * v0 is the system call number, except for O32 ABI syscall(), where it + * ends up in a0. + */ + if (mips_syscall_is_indirect(task, regs)) + task_thread_info(task)->syscall = regs->regs[4]; + else + task_thread_info(task)->syscall = regs->regs[2]; +} + +static inline unsigned long mips_get_syscall_arg(unsigned long *arg, + struct task_struct *task, struct pt_regs *regs, unsigned int n) +{ + unsigned long usp __maybe_unused = regs->regs[29]; + + switch (n) { + case 0: case 1: case 2: case 3: + *arg = regs->regs[4 + n]; + + return 0; + +#ifdef CONFIG_32BIT + case 4: case 5: case 6: case 7: + return get_user(*arg, (int *)usp + n); +#endif + +#ifdef CONFIG_64BIT + case 4: case 5: case 6: case 7: +#ifdef CONFIG_MIPS32_O32 + if (test_tsk_thread_flag(task, TIF_32BIT_REGS)) + return get_user(*arg, (int *)usp + n); + else +#endif + *arg = regs->regs[4 + n]; + + return 0; +#endif + + default: + BUG(); + } + + unreachable(); +} + +static inline long syscall_get_return_value(struct task_struct *task, + struct pt_regs *regs) +{ + return regs->regs[2]; +} + +static inline void syscall_rollback(struct task_struct *task, + struct pt_regs *regs) +{ + /* Do nothing */ +} + +static inline void syscall_set_return_value(struct task_struct *task, + struct pt_regs *regs, + int error, long val) +{ + if (error) { + regs->regs[2] = -error; + regs->regs[7] = 1; + } else { + regs->regs[2] = val; + regs->regs[7] = 0; + } +} + +static inline void syscall_get_arguments(struct task_struct *task, + struct pt_regs *regs, + unsigned int i, unsigned int n, + unsigned long *args) +{ + int ret; + + /* O32 ABI syscall() */ + if (mips_syscall_is_indirect(task, regs)) + i++; + + while (n--) + ret |= mips_get_syscall_arg(args++, task, regs, i++); + + /* + * No way to communicate an error because this is a void function. + */ +#if 0 + return ret; +#endif +} + +extern const unsigned long sys_call_table[]; +extern const unsigned long sys32_call_table[]; +extern const unsigned long sysn32_call_table[]; + +static inline int syscall_get_arch(void) +{ + int arch = AUDIT_ARCH_MIPS; +#ifdef CONFIG_64BIT + if (!test_thread_flag(TIF_32BIT_REGS)) { + arch |= __AUDIT_ARCH_64BIT; + /* N32 sets only TIF_32BIT_ADDR */ + if (test_thread_flag(TIF_32BIT_ADDR)) + arch |= __AUDIT_ARCH_CONVENTION_MIPS64_N32; + } +#endif +#if defined(__LITTLE_ENDIAN) + arch |= __AUDIT_ARCH_LE; +#endif + return arch; +} + +#endif /* __ASM_MIPS_SYSCALL_H */ |